BCAAs Vs EAAs – The Battle for Your Gains

BCAAs Vs EAAs – The battle of the ages? Not really. The winner is pretty clear-cut. Read on, and you’ll find out which supplement of these two that gets to wear the StrengthLog crown.

One of the most common questions about supplements we get is: what’s the difference between EAAs and BCAAs, and which one is the best? In our big BCAA article, we delve deep into this topic, but some readers think it’s too heavy and difficult a read.

There might be something to that! Understanding how protein and amino acids work can be tricky if you don’t have any previous knowledge. At StrengthLog, we want you to be able to get all the info about training and nutrition you need without having to leave the site.

Here, you’ll get all the info you need about EAAs and BCAAs in an easy-to-read article, without the need for any previous knowledge. After reading it, you’ll know what EAAs and BCAAs are and which is the best option to build muscle.

Protein: The Building Blocks of Your Body

Proteins are nutrients and building blocks for your body. Not just for your muscles, but your organs, your skin, your tendons and ligaments, your gut, and your intestines, too. Also, you use protein to make enzymes and hormones. All the cells in your body need protein to work properly.

When you think about protein, you probably think about something in the food you eat. While that is true, you are also made up out of protein. If you remove the water and the fat from your body, the rest is almost entirely made out of proteins.

Amino Acids, What Are They?

So, your body is built on the foundation of protein. Protein, in turn, is made up of amino acids. There are twenty of them. Amino acids are little building blocks, too, connected in chains that form proteins.

When you eat a protein-rich meal, your digestive system breaks these chains down into free amino acids. They are then absorbed into your bloodstream from the intestine and travel to places in your body that need some new cells constructed or some old ones repaired.

Amino acids come in two categories: essential amino acids and non-essential amino acids.

Essential Amino Acids (EAAs)

The essential amino acids are the ones your body can’t make on its own. You need to get them from the food you eat. There are nine essential amino acids, and they all have complicated names. They are, in alphabetical order:

  • Histidine
  • Isoleucine
  • Leucine
  • Lysine
  • Methionine
  • Phenylalanine
  • Threonine
  • Tryptophan
  • Valine

In addition to those, there is an amino acid called arginine. That one is essential for children. This means that kids need to get arginine from food, but your adult body can produce it as needed.

Essential Amino Acids are abbreviated as EAAs.

Non-Essential Amino Acids (NEAAs)

Since the protein you eat is made up of 20 amino acids, and 9 of these are essential, that leaves 11 more amino acids. These are non-essential amino acids. You can make them in your body, so you don’t necessarily have to get them from food.

The list of non-essential amino acids looks like this:

  • Alanine
  • Arginine
  • Asparagine
  • Aspartic acid
  • Cysteine
  • Glutamic acid
  • Glutamine
  • Glycine
  • Proline
  • Serine
  • Tyrosine

Even if you don’t need to get these amino acids from your diet to stay healthy and build muscle, you get them anyway, whether you want to or not. You get them all, often in abundance, from all the protein you eat.

Non-Essential Amino Acids are abbreviated as NEAAs.

Supplementary Study: Conditionally Essential Amino-Acids

Out of the non-essential amino acids, six are conditionally essential. What does this mean? It means, as the name implies, that they are essential under certain conditions, like stress and illness.

When your body is extremely stressed or subjected to things that cause tissue breakdown, it needs more amino acids than usual to repair itself. If that happens, your body might not be able to keep up with the demand for non-essential amino-acids.

One example of a conditionally essential amino acid is glutamine. Normally, your body has no problem making all the glutamine it needs. You make quite large amounts of glutamine, in fact, between 40 to 80 grams daily.

Under normal conditions, that’s more than enough.

However, if your body is subjected to high levels of stress, or if you are very sick, even those amounts are not enough. When that happens, it uses up more glutamine than it can make. You have to get more, either from your diet or from a supplement. Suddenly glutamine becomes an essential amino acid.

Strength training and other everyday activities are not counted as very stressful things. We’re talking about severe burns, intestinal or gut surgery, and sepsis, things like that. Don’t listen to supplement retailers telling you that you need a glutamine supplement to recover from your strenuous training. That’s not the case, no matter how gut-busting your workouts are.

Also, glutamine is the most abundant amino acid in all your regular protein-rich foods.

Branched-Chain Amino Acids (BCAAs)

There are three branched-chain amino acids. There is a lot of confusion about the difference between them and EAAs. Let’s untangle the amino acid mess.

What’s the Difference Between BCAAs and EAAs?

There is none. BCAAs are EAAs.

Does that sound weird and complicated? It’s not. It’s much simpler than it might sound.

BCAAs aren’t any other amino acids than the ones you saw in the list of essential amino acids earlier. They are simply three of those: leucine, isoleucine, and valine.

These three amino acids are both essential and branched-chain. Branched-chain means that they have a chemical structure that makes them look like little trees with branches.


The other essential amino acids don’t have this branch-looking structure. “BCAA” is just a way to describe the structure of leucine, isoleucine, and valine. They are just three of the nine essential amino acids, but with a special structure that looks like a canopy of branches.

EAAs, BCAAs, and Your Muscles

If you didn’t skip to this part because you saw the word “muscles” in the sub-heading, you already know that you only need to get the essential amino acids from your diet. This holds when it comes to building muscle as well.

You require all the 20 amino acids to build new muscle mass, but your body can make the non-essential ones as needed. The non-essential amino acids in a protein-rich meal make no difference. Studies show that 10 grams of essential amino acids build just as much muscle as 10 grams of essential amino acids plus 10 grams of non-essential.

Even disregarding the fact that your body can make non-essential amino acids when it needs them, you get plenty of them from all the protein you eat. You don’t need to think about the non-essential amino acids or wonder how you’re going to get enough of them.

Not All the Protein You Eat Builds Muscle

The protein and amino acids you eat don’t automatically travel through your body to your arms and make your biceps bigger. Far from it. Only 10–11% of the protein you eat ends up as muscle protein. You use the rest to build and repair other cells than muscle cells. Also, your body can convert most of the amino acids into glucose, if needed.

You might have heard the number 2 grams of protein per kilogram of body weight and day floating about when it comes to building muscle. This is indeed a good amount of protein to aim for if you want to build muscle effectively.

This means that you want to get 160 grams of protein every day if you weigh 80 kilograms. But why eat that much protein, if only 10–11% of it becomes muscle?

That’s because getting a lot of protein gives your muscles better opportunities to grow. You see, the protein you eat is not your only source of amino acids.

How Your Muscles Use Protein and Amino Acids to Grow Bigger

Most of the amino acids you use to build muscle come from your muscles, from muscle protein breakdown.

Muscle breakdown sounds like a bad thing to be avoided at any cost. It isn’t, not as long as you are healthy and eat enough. You break down a lot of muscle every day. That’s just business as usual and how your body, your muscle protein metabolism, works. It doesn’t mean that the amino acids are lost. You recycle them and use them to build new muscle tissue.

When you eat protein, it breaks down into free amino acids in your gut and intestines. From there, they enter your bloodstream. When a lot of amino acids suddenly appear in your blood, your body thinks, “Building material for my muscles! Better get to work!”

In other words, your body reacts to high levels of amino acids in the blood, like after you’ve eaten a protein-rich meal, and starts building muscle. These signals set off complicated mechanisms that add amino acids to your muscle tissue, leading to muscle growth in the long run.

The amino acids that end up as new muscle tissue don’t have to come from the protein you just swallowed and which started the process of building muscle, a process called muscle protein synthesis.

The amino acids from the muscle protein you break down all day long are alerted by the high level of amino acids in your blood. They are then transported to your muscle cells, where they help create new muscle protein. Only a small amount of the muscle protein you break down disappears from this turnover of amino acids. Most of the amino acids released from broken-down muscle protein are recycled and used to build muscle again.

Enter BCAAs

Let’s recap: when a lot of amino acids enter your blood in a short amount of time, they turn on signals telling your body to build muscle.

However, not all amino acids are responsible for this effect. The branched-chain amino acids, BCCAs, are the most potent here. Leucine in particular is the amino acid that triggers the entire process. If too little leucine shows up in your blood, not much of anything happens. You stimulate muscle protein synthesis to the max if you eat a protein-rich meal containing about 2.5–3 grams of leucine. If your meal provides you with less leucine, you still build muscle, but not as much of it.

All protein you eat contains BCAAs. If you enough protein in one sitting to get 2.5–3 grams of leucine, that meal stimulates your muscle protein as much as possible.

Whey protein is the protein with the most leucine. About 25 grams of whey protein stimulates muscle protein synthesis maximally. Other proteins give you a little less leucine per 100 grams, which means that you need more of it to get the same muscle-building effect.

Animal proteins, like eggs, meat, poultry, dairy, and fish, provide more of the essential amino acids, including BCAAs and leucine, than plant-based proteins. If your meals are entirely plant-based, you need to increase the amount of protein in your meals, if you want them to build as much muscle as possible. For example, you need to eat 38 grams of pea protein, 40 grams of soy protein, or a whopping 54 grams of hemp protein to get the same anabolic effect as you get from 25 grams of whey protein.

Amino Acids From Food Vs Supplements

You never need to get your amino acids, essential or non-essential, BCAAs or any other, from amino acid supplements. The protein in the food you eat contains all the amino acids. If you use a protein powder supplement, that too gives you all the 20 amino acids, including the BCAAs.

BCAA Supplements Vs EAA Supplements

This is the part of the article a lot of you probably are most interested in. So you’ve decided you want an amino acid supplement. What should you choose? A BCAA supplement or a supplement with all nine EAAs? Maybe protein powder? Which is the best choice?

BCAA Supplements

As for BCAA supplements, it’s not that difficult. BCAA supplements are more or less money down the drain.

As we said earlier, BCAAs, especially leucine, turn on your muscle protein synthesis. Of course, this means that it’s easy to think that BCAA supplements are a must-have, or at least useful.

That is not the case. BCAA supplements aren’t effective at all compared to a supplement providing all the essential amino acids or compared to protein powder. Let’s sort things out.

BCAA Supplements on an Empty Stomach

BCAAs are often marketed as supplements you should take on an empty stomach, maybe before a workout or in between meals, to stimulate muscle protein synthesis.

The problem is that BCAAs alone do not stimulate muscle protein synthesis. At least not to any particular degree. When you take BCAAs on an empty stomach, you DO stimulate muscle protein synthesis, but only 20 % more than sugar. Not a whole lot, in other words. The effect is 50 % below what you get from whey protein providing the same amount of BCAAs.


Even though BCAAs, with leucine as the flag bearer, turns muscle protein synthesis on, you need the other essential amino acids for something to happen. Without them, as we discussed earlier, you only have amino acids from broken down muscle protein for building blocks.

If your body doesn’t have access to any other amino acids than those, you can never build more muscle than you break down. At best, you only recycle the amino acids you already have available. But the very purpose of your workouts is to build more muscle mass, not just maintain what you have. And a BCAA supplement won’t and can’t cut it.

BCAA Supplements Along With Regular Protein

But what if you take the BCAAs along with another protein source providing the other essential amino acids?

Unfortunately, that won’t work either.

If you get BCAAs (read: leucine) from a regular protein source in amounts that stimulate muscle protein synthesis decently, nothing happens if you add even more BCAAs. You already have enough leucine. And enough is just that: enough.

What if you don’t get enough BCAAs from a meal? If you eat something low in protein? It does feel logical that adding a BCAA supplement would boost muscle protein synthesis in that case.

Again, unfortunately, this doesn’t happen.

If you do that, the BCAAs from the supplements compete for the uptake from your intestines with the amino acids from the meal. The result? Lower levels of amino acids in the bloodstream than expected and no extra effect from the BCAA supplement.


As you can see in the image above, pure leucine works where all three BCAAs don’t. You can add leucine to a meal low in protein to boost muscle protein synthesis. But then why not just eat more protein?

In any case, BCAA supplements don’t build muscle or increase muscle protein synthesis the way supplement manufacturers would like you to believe they do. Not on an empty stomach and not together with a meal.

EAA Supplements

Unlike supplements providing only the three branched-chain amino acids, a supplement with all nine essential amino acids works just fine. That’s proven beyond the shadow of a doubt in numerous controlled studies. The essential amino acids are the amino acids you need to build muscle, after all, and you get all of them from an EAA supplement. That supplement includes the BCAAs, for that matter.

If you want to use an EAA supplement, go right ahead.

That said, you can simply eat regular protein-rich meals or use a protein supplement instead. Those options also give you all the EAAs and BCAAs you need. And you get the non-essential amino acids as well, meaning your body doesn’t have to spend energy making them.

Also, food and protein powder taste better. EAA-supplements have a terrible taste. “But my EAA supplement tastes great and refreshing” you might say. No, your EAA supplement tastes like sewage. That refreshing taste is the taste of enough flavoring agents and sweeteners to hide the real taste of the amino acids.

What’s more, you don’t use the protein you eat just to build muscle. Far from it. Protein is the most important nutrient for basically everything that happens in your body.

An EAA supplement might be a good idea if you’re on a really strict diet where every calorie counts. Since you get the same muscle-building effect from 10 grams of EAAs as from 20–25 grams of protein, you save a dozen or so calories there. As you probably remember, the non-essential amino acids don’t provide any additional anabolic effect.


For the most part, there are few reasons to choose an amino acid supplement instead of a protein supplement or a protein-rich meal. You build just as much muscle from X grams of essential amino acids from those options as from X grams of essential amino acids from an EAA supplement. Don’t fall for marketing telling you otherwise.

  • EAAs – essential amino acids – are the amino acids you have to get from your diet.
  • BCAAs – branched-chain amino acids – are three of the essential amino acids.
  • All protein in the food you eat contains all amino acids, including EAAs and BCAAs.
  • BCAA supplements are more or less a waste of money.
  • EAA supplements “work”, but you get as good or better an effect from regular food or a protein powder.


Looking for references to anything you’ve just read? You’ll find them all in StrengthLog’s big guide to everything BCAA!